Huperzine A is a plant alkaloid derived from Club moss plant, Huperzine serrata, which is a member or the Lycopodium species. Huperzine-A is in phase III clinical trial in the USA (Alzheimer disease) and is available as a dietary supplement. It selectively and reversibly inhibits acetylcholinesterase. Huperzine A is also a NMDA receptor antagonist, which protects the brain against glutamate induced damage, and it increases nerve growth factor levels. Huperzine A is used for Alzheimer's disease, memory and learning enhancement, and age-related memory impairment. It is also used for treating a muscle disease called myasthenia gravis, for increasing alertness and energy, and for protecting against agents that damage the nerves such as nerve gases. It can cause some side effects including nausea, diarrhea, vomiting, sweating, blurred vision, slurred speech, restlessness, loss of appetite, contraction and twitching of muscle fibers, cramping, increased saliva and urine, inability to control urination, high blood pressure, and slowed heart rate. Various medications used for glaucoma, Alzheimer's disease, and other conditions (Cholinergic drugs) interacts with Huperzine A.

Velnacrine (9-amino-1,2,3,4-tetrahydroacridin-1-ol) is an inhibitor of acetylcholinesterase. It was studied for the treatment of Alzheimer's disease however development was discontinued. There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy.

Fenproporex is a central and indirect-acting sympathomimetic. It was developed as an anorectic drug. Their anorectic effects are believed to be a result of adrenergic activation. Fenproporex has never been approved by the US Food and Drug Administration (FDA) for sale in the US due to lack of efficacy and safety data. There is a paucity of randomized, placebo-controlled trials on Fenproporex. These studies suggest that Fenproporex is modestly effective in promoting weight loss. Data from these studies are insufficient to determine the risk-benefit profile of Fenproporex. Abuse potential and amphetamine-like adverse effects are causes for concern. Adverse effect most frequently reported are: insomnia, anxiety, depression, irritability, dry mouth.

Huperzine A is a plant alkaloid derived from Club moss plant, Huperzine serrata, which is a member or the Lycopodium species. Huperzine-A is in phase III clinical trial in the USA (Alzheimer disease) and is available as a dietary supplement. It selectively and reversibly inhibits acetylcholinesterase. Huperzine A is also a NMDA receptor antagonist, which protects the brain against glutamate induced damage, and it increases nerve growth factor levels. Huperzine A is used for Alzheimer's disease, memory and learning enhancement, and age-related memory impairment. It is also used for treating a muscle disease called myasthenia gravis, for increasing alertness and energy, and for protecting against agents that damage the nerves such as nerve gases. It can cause some side effects including nausea, diarrhea, vomiting, sweating, blurred vision, slurred speech, restlessness, loss of appetite, contraction and twitching of muscle fibers, cramping, increased saliva and urine, inability to control urination, high blood pressure, and slowed heart rate. Various medications used for glaucoma, Alzheimer's disease, and other conditions (Cholinergic drugs) interacts with Huperzine A.

Trichlorfon (Metrifonate), the organophosphorous cholinesterase inhibitor, O,O-dimethylhydroxy-2,2,2-trichlorethyl-phosphonate, has been used sporadically in the treatment of human schistosomiasis for a decade. It has selective and variable schistosomicidal activity against S. haematobium that results from its partial metabolism to a highly active anti-cholinesterase, dichlorvos. Schistosomal cholinesterase is more susceptible to this metabolite than that of the human host, but transient reductions in both plasma and erythrocyte cholinesterase activity are demonstrable at therapeutic dosage. However, despite early concerns about its potential toxicity, metrifonate is well tolerated and has been used effectively and extensively in large-scale control programmes. Its potential to enhance central nervous system cholinergic neurotransmission led to clinical trials for the treatment of people with Alzheimer's disease (AD).

Trichlorfon (Metrifonate), the organophosphorous cholinesterase inhibitor, O,O-dimethylhydroxy-2,2,2-trichlorethyl-phosphonate, has been used sporadically in the treatment of human schistosomiasis for a decade. It has selective and variable schistosomicidal activity against S. haematobium that results from its partial metabolism to a highly active anti-cholinesterase, dichlorvos. Schistosomal cholinesterase is more susceptible to this metabolite than that of the human host, but transient reductions in both plasma and erythrocyte cholinesterase activity are demonstrable at therapeutic dosage. However, despite early concerns about its potential toxicity, metrifonate is well tolerated and has been used effectively and extensively in large-scale control programmes. Its potential to enhance central nervous system cholinergic neurotransmission led to clinical trials for the treatment of people with Alzheimer's disease (AD).

Velnacrine (9-amino-1,2,3,4-tetrahydroacridin-1-ol) is an inhibitor of acetylcholinesterase. It was studied for the treatment of Alzheimer's disease however development was discontinued. There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy.

Velnacrine (9-amino-1,2,3,4-tetrahydroacridin-1-ol) is an inhibitor of acetylcholinesterase. It was studied for the treatment of Alzheimer's disease however development was discontinued. There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy.

Velnacrine (9-amino-1,2,3,4-tetrahydroacridin-1-ol) is an inhibitor of acetylcholinesterase. It was studied for the treatment of Alzheimer's disease however development was discontinued. There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy.

Velnacrine (9-amino-1,2,3,4-tetrahydroacridin-1-ol) is an inhibitor of acetylcholinesterase. It was studied for the treatment of Alzheimer's disease however development was discontinued. There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy.